Odormeter



Aug. 17, 1943.

A. POLLAK ETAL ODORMETER Filed March 18, 1941 INVENTORS filer-awe @4446 Taro/ms r9 MZM/Gbfi"? BY 2 I A'i'ToRNEY Patented Aug. 17, 1943 4 2,327,060: ODORMETER Arthur Pollak, New York, N. Y., and Thomas A. Willingham, Charleston, S. 0., assig-nors to West Virginia Pulp and Paper Company, New York, N. Y., a corporation of Delaware Application March 18, 1941, Serial No. 383,924

4 Claims.

Our present invention has to do with a device and method for evaluating odors. Various in,- dustrial processes give rise to odors in the neighborhood surrounding the plant or factory in which the process is being carried on, such process es being for the most partthe subject of study to determine ways and means for abating the odor. In order to measure results obtained by such ways and means, it is desirable to know quantitatively what degree of abatement, if any, for example, may result from a given operation having as its object the amelioration of the odor.

It is therefore an object of our invention to devise an odormeter by means of which an odor may be quantitatively determined, whereby the odor' in a given locality may be compared with that in another. are remarkably sensitive to certain odors, there is no way in which the olfactory sense, unaided, may determine the intensity or concentration of such odors.

A still fur-ther object of our invention is to pro vide an o'dormeter which is compact and portable.

Other objects to be attained and the advantages thereof will be apparent as the description proceeds, reference being had to the ensuing detailed description taken with the annexed drawing, in which the single figure shows diagrammatically the apparatus employed in an illustrative embodiment.

In carrying out our invention we provide preferably a source of air which is entirely uncontaminated and which may be stored under pressure in a suitable container. Means are provided whereby this air is breathed by the operator so as to rest the olfactory nerves until such time as they are sensitive to the odors (if any such exist) of the surrounding air (or of the air being tested); it also has the purpose of diluting the ambientair down to the threshold value. Also, a feature of my invention is the means to introduce at will in the region of the nostrils of the operator, portions of the diluted ambient air whereby such air is inhaled for very brief periods 14, valve I5, filter I6 containing activated car- .bon, pipe II, to mask I8. From said mask the air passes through flexible tube I3 and out of the system through apressure regulator 20. The

While the olfactory nerves pipe I2 branches off into the pipe 2| ahead of valve l4 and conducts a portion of they pure air at a slightly higher pressure than that passing through filter I6, through a valve 22 and a filter 23, thence through valve 23a to a flowmeter 24 of known construction. Pipe 2| also has a pressure control device 24a whereby sudden increases in pressure are prevented from overloading the meter 24. From meter 24 the air passes through a flexible tube 25 leading to a mask I8. Air is respirated from the mask and is exhaled into the mask and leaves the same through pipe I9 into pressure regulator I8 above mentioned, and thence out to the atmosphere.

Polluted air, as for example the circumambient air, passes through blower 3|, pipe 32, valve 33, flowmeter 34 similar to fiowmeter 24. In thi line is also a pressure regulator 34a similar to regulator 24a. A stream of the polluted air passing through the pipe 32 is'diluted by a stream or the 38 within the mask.

A differential manometer 40 has one leg 4| connected to pipe I9 in the circuit of the purified air, while the other leg 42 is connected to the pipe 22a through which the air to be tested is flowing. Thus the operator can at all times make sure that the pressure in the mask from the source of pure air is greater than that: of the impure air to be tested so that no air escapes through the holes 38 until such time as the operator stops the end 39 of tube 36 as with his finger, whereupon sufllcient pressure is ,built up in the tube 36 to permit the diluted stream of polluted air to pass through the holes 38 into the proximity of' the nostrils of the operator.

The operation of our improved device is fairly apparent from the foregoing. The operator adjusts the valves 23a and '33 so as to give the, maximum or threshold dilution of the air in the pipe 32, which will be detectable by the operator. The operator thereupon notes' the readings of the two fiowmeters 24 and 34 and calculates the rate of flow througheach. The odor intensity or concentration is then most conveniently expressed by the relationship flow rate of pure air plus odorous gas 7 po=log (i. e., flow through 24 plus flow through 34) flow rate of odorous gas.

This value for hydrogen sulfide is.

6.11, for ammonia. 4.3 whereasior a gas which is inodorous or substantially so the p value will be or very nearly 0.

It will berobvious that, as described, the odormeter actually measures the concentration of the odorous substance in either the ambient air or a source other than the ambient air. Ii. the latwith the ambient air (for example, where the ambient air is without odor), instead of using compressed air in the bottle ill the blower 43 is used to pump the ambient air throughthe system comprising the lines i2, 2 I etc.

A further field of application of our improved odormeter is that of air conditioning. When air and odorous substances accumulates, and it is desirable to have a quantitative measure of these, for which purpose our improved device is well adapted.

It will be understood that various changes may be made in the embodiment described in the foregoing which do not depart from the spirit of our invention or the scope of the appended claims...

We claim: 1. The method of estimating the concentration of odor in a gas, which comprises'continuously diluting a stream of the gas to be tested with pure air, admitting substantially continuously to a region confining the nose of the operator, pure as air for breathing from a source other than the ambient air, conducting the diluted gas to said confined region, momentarily displacing the air therein with said diluted. gas while olfactorily testing same,-varying the amountoi dilution of said odorous gas until, when oliactorlly tested in said confined region, the threshold value is reached, and measuring the degree of dilution of said gas at said threshold value.

2.1In an odormeter adapted for use in the measurement of the odor of the ambient air, a breathing device adapted toins'ulate the breathing orifices of the observer from theambient air,

a source or supply thereto or relatively pure air for breathing, means for passing an odorous gas thereto to be tested, means fordiluting the odorous gas with pure air from said source prior to the admission or such diluted odorous gas to 4 said breathing device, a flow measuring device for said odorous gas, a flow measuringdeviceior said air for dilution, and means for admitting at will and for brief intervals said diluted odorous gas to said breathing device whereby the nostrils oi the observer are purged or the odorous gas by air from said source 0! relatively pure air except at such short intervals when the diluted odorous gas is breathed.

3. In an odormeter, a. mask adapted to insulate the breathing o'rifices of the observer from the ambient air, and for permitting the breathing of samples oi air to be tested, means for passing an odorous gas thereto, means for diluting the odorous gas with pure air prior to its admisis recirculated sufiiciently a residue of impurities sion to said breathing device, means to measure the how of said odorous gas and means to measure the. flow or said air for dilution and means 1 for admitting at will said odorous gas to said mask, said means comprising a tube passing through said mask and egtending open-ended beyond the same and being perforated within said mask whereby said diluted odorous air escapes into said mask only when its pressure is greater than that of said pure air, as when saidopen end is obstructed. l

4. The-method of estimating the concentration or. odor in the ambient air which comprises continuously diluting a stream or said ambient air with pure air from a source provided, admitting substantially continuously to a region confining the nose or the operator a stream or said pure air for breathing, conducting the so-diluted ambient air to said confined region, momentarily dis- 0 placing the pure air therein with said diluted ambient air while olfactorily testing same, varying the amount of dilution oi said ambient air until, when oliactorily tested in said confined re-.

gion, the threshold value is reached, and messuring 'the degree of dilution of said ambient air ARTHUR POLLAK.

at said threshold value.

I THOMAS A. wmimanam. 

